Electric-lamp base



E. B. WQLCOX.

ELECTRIC LAMP BASE.

APPLlCATlON FILED JUNE 30, 1919.

1,368,590. -Patenfed Feb. 15,1921.

UNITED s A'rss PATIENT OFFICE.

WILCOX, OF MERIDEN, CONNECTICUT.

. J CTRIC-LAMP BASE.

To all whom z'tmay concern: Q

Be it known thatI, EDSON B. WILoox, a citizen of the United States of America, residing at Meriden, Connecticut, have invented a new and useful Electric-Lamp Base, of which the following is a specification.

My invention relates to electric connectors and particularly electric lamp bases of the type of my Patent #1,159,456of November 9th, 1915.

The main object is to provide a simple form of construction of this ty e which can be made economically. Anot er object is to provide a construction of this type which is more durable and less subject to accidental injury. Another object is to provide means for automatically severing the connection in case of short circuit. Another object is to prevent a central plunger from contacting with both end terminals at the same time. i i

In carrying out these'objects in the pre ferred manner, the two eyelet members with the soldered filament connections constitute the three end terminals. One of the eyelets is located a little nearer the center of the base than the other and projects into a plane somewhat beyond the other so that it is adapted to be engaged at its inner edge by the center plunger of a single wire type socket, or at its outer edge by one of the plungers of a two-wire typeof socket. The other eyelet member is connected to the outer sleeve by, a fusible wire so'that the connection will ,be. automatically severed in case of a ground and short circuit in a twowire system. This fuse wire is preferably located in a groove in the insulating material of the base so that it is protected against accidental injury.

Figure 1, is a side view of an incandescent lamp and base embodying the improve ments of my invention. g

I Fig. 2, is an end view of the same.

Fig. 3, shows the lamp in conjunction withcontact plungers of a two-wire circuit.

Fig. 4., shows the lamp in conjunction with the plunger and socket of a single wire system. I y

Fig. 5, is an enlarged sectional view of the lam base.

Fig. 6, is an end view of the same.

The filament 10 and bulb 11 are of any suitable types. The end terminals 12 and 13 are connected to the circuit wires such as Specification of Letters Patent.

' Application and June so;

Patented Feb. 15, 1921.

11919. Serlal No. 307,678.

the ends of the filament of the lamp.

These terminals may be conveniently formed by embedding metal eyelets 12 and 13" in the insulating material 14 of the base. The

endsof the filamentmay be soldered to these eyelets and a globule of solder permitted to extend beyond the eyelets to form the rounded contacts. The outer sleeve 15 surrounds the insulating material 14 and connectsthe parts to the neck of the bulb.

The end terminal 12 constitutes the central contact and one of the side contacts at the rear end of the plug. The end contact, or terminal 13, is connected to the side con tact or sleeve 15 by a fusible wire 16.

Preferably a part 17 of the insulating base 14. projects beyond the remainder of the base so as to hold the terminal 12 in a plane beyond the plane of the terminal 13. The end of the sleeve 15 is flanged over at 18 to embrace the insulating material and the wire 16 'is preferably connected adjacent thereto. By locating the fuse wire 16 in the groove 16 between the two end terminals 12 and 13, the wire is protected against accidental injury. The angle or space between the raised part 17 and the remainder of the base constitutes the protecting groove 16, in the preferred form.

When the lamp is inserted in the socket of a two-wire or all-wire system, the two plungers of the ordinary socket 20 and 21 engage the terminals 12 and 13 as shown in Fig. 8, the plunger 20 engaging the outer part of the terminal 12. When using the lamp in the two-wire system, the wire 16 should be severed as it is unnecessary and may occasion a ground or short circuit. In case the wire 16 is not intentionally severed in such a system and a ground, or short circuit occurs, the wire 16 being fusible will be automatically severed.

If the lamp is inserted in the socket of a single wire or grounded type system, the ordinary central plunger 22 engages the inner part of the terminal 12 and the sleeve 23 of the socket engages the sleeve 15 of the lamp, as shown in Fig. 4. By having the terminal 12 project beyond the end of: the terminal 13 there is no danger of the central plunger 22 engaging both terminals even it the plunger is large enough in diameter to overstand the edge of the outer end terminal 13. V

It will thus be seen that this improved form of device may be used either in a single or two-wire system interchangeably, and independently of the diameter of the central plunger.

The terminal 13 constitutes one outer end terminal. The terminal 12 constitutes two end terminals, the outer portion being an outer end terminal, and the inner portion being an inner end terminal. The sleeve portion 15 may be designated a side terminal.

I claim 1. In a device of the class described adapted for use in a single or a two-wire system, a base having two endterminals connected to the ends of a circuit wire, one of which terminals is nearer the center than the other and projects beyond the other, and a sleeve terminal electrically connected to the outer of the end terminals by means of a fusible wire, for the purpose described.

2. In an electric connector adapted for use in a single or a two-wire socket, an insulating base having one portion of the end projecting in a plane beyond the other portion of the end, end terminals carried by said two portions of the base, a side terminal on said base, and a connect-ion between said side terminal and one end terminal, said portions of the end of the base being in different planes to permit only one of said terminals to be engaged by a single wire socket.

In an electric connector, an insulating base having two terminal members, one

of which is located nearer the axis of the base than the other terminal and has a hearing face in a plane beyond the plane of the other terminal, and an outer side terminal connected to the other of the end terminals by a fusible wire whereby when said connector is used in a two-wire system and a short circuit occurs, said fusible wire will be automatically severed.

a. In a device of the character dcscribml. an insulating base, a side terminal on said base, one side of the end portion ot said base projecting in a plane beyond the plane of the other side of the end portion, end terminals carried by said portions. and a fusible connection between said side terminal and one end terminal, for the purpose e described.

EDISON B. WILCOX. 

